Evelyn Owen Tinkered Until He Found the Right Caliber for His Carbine

The .32 ACP Owen Gun. Australian War Memorial photo The Owen Gun first appeared in .32 ACP by MATTHEW MOSS Australia’s Owen Machine Carbine was one of the most...

The .32 ACP Owen Gun. Australian War Memorial photo

The Owen Gun first appeared in .32 ACP

by MATTHEW MOSS

Australia’s Owen Machine Carbine was one of the most reliable and effective submachine guns of World War II. It’s not widely known that developer Evelyn Owen chambered an early prototype of the carbine in .32 ACP, rather than the nine-by-19-millimeter cartridge that became standard for the weapon.

Owen began work on his design in 1938, hand-building a .22LR-caliber prototype with an unusual drum magazine. Working at the Lysaght factory in Port Kembla, Owen gradually evolved the carbine, switching the type and placement of the magazine and repeatedly rechambering the weapon, from .22LR to .32 ACP, .38-200 and .45 ACP — and finally to the definitive nine-by-19 millimeter.

The .32 ACP prototype loaded from the side, unlike the final Owen Gun, which had a top-mounted magazine. The 30-round magazine fit into the left side of the receiver and angled slightly down and to the rear. Presumably Owen meant this to aid reliable feeding.

The .32 ACP prototype shares some of the features of the production model, including the pistol grips with two finger grooves and the tubular receiver.

On the prototype, the butt and trigger mechanism could be released by a spring clip on the right of the receiver. The barrel was also held in place by a spring clip. Owen eliminated these spring clips from the final version of the gun — and also shortened the weapon’s receiver.

The Owen Gun underwent trials with the Australian army in 1942. By 1945, Lysaght had made 45,000 Owen Guns for the Australian military. They proved extremely reliable and remained in service into the 1960s.

The Owen Machine Carbine saw action with Australian and New Zealand troops during World War II, in Korea and during the Malayan Emergency, the Indonesian Confrontation and the Vietnam War.